. Eutherian mammals are uniquely defined by

A. having a placenta.
B. longer gestation periods because of more highly developed placentas.
C. having fur.
D. the young developing in a pouch.
E. laying eggs.


B. longer gestation periods because of more highly developed placentas.

Biology & Microbiology

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Which of the following statements concerning the

peripheral nervous system is false? a. Spinal nerves lead to and from the spinal cord. b. There are 31 pairs of spinal nerves. c. Cranial nerves connect directly to the brain d. Peripheral nerves include axons from numerous neurons. e. All spinal nerves carry only motor fibers.

Biology & Microbiology

Which simple sugar is the main energy source for body cells?

a. fructose b. sucrose c. lactose d. glucose e. galactose

Biology & Microbiology

If a trait has a heritability of 0.5, this means that

A. all variation in the population is caused by genotypic differences. B. all variation in the population is caused by environmental differences. C. the variation in the population is the result of epigenetic effects. D. the genotype and environment contribute equally to the variation seen in the population. E. None of these is true.

Biology & Microbiology

Changes in behavior that result from environmental experiences are called:a

instincts. b. learned behaviors. c. proximate causes. d. ultimate causes. e. innate behaviors

Biology & Microbiology